JP5560657B2 - Image forming apparatus - Google Patents

Description

The present invention is a sheet-like recording medium that has been conveyed (herein referred to as "sheet") copying machine provided with a sheet stacking equipment for stacking, a printer, a facsimile, an image forming apparatus such as a digital multifunction peripheral .

  Various paper loading positions are set according to the use and configuration of the image forming apparatus and the image forming system. Among them, there is an invention configured to provide a stacking unit for sheets discharged in a limited space and to secure a stacking amount. Among them, for example, the invention described in Patent Document 1 (Japanese Patent Laid-Open No. 2008-110834) is known as a paper stacking position above the image forming apparatus and below the image reading apparatus. is there. This patent document 1 discloses an image forming apparatus in which a recording sheet material on which an image is formed by an image forming unit is discharged from a discharge unit of the image forming apparatus to an in-body discharge unit having a discharge tray. The discharge tray has a stacking surface on which the recording sheet material discharged from the discharge portion is stacked, and the discharge tray is disposed in the discharge direction of the recording sheet material discharged from the discharge portion. There is disclosed an invention characterized in that an angle changing means is provided for making the angle of the stacking surface of the paper tray closer to the discharge section to be variable.

  Further, for example, Patent Documents 2 to 5 disclose an invention in which the entire tray is provided so as to be movable up and down by a motor. Among these, in Patent Document 2 (Japanese Patent No. 4072515), an image forming unit that forms an image based on image information on a recording sheet that is conveyed, and the image forming unit are arranged above the image forming unit. A scanning device that scans a document and reads image information; a sheet stacking unit that stacks discharged sheets; and a space between the image forming unit and the scanning device. And a sheet discharging unit that discharges the sheet to the sheet stacking unit. The image forming apparatus includes a driving unit that has a motor to raise and lower the stack unit, and a surface on which the sheets of the stack unit are stacked is , Inclining so that the downstream side in the transport direction of the bundle transport means is upward, below the surface on which the sheets of the stack means are stacked, and below the transport direction of the bundle transport means Invention, wherein the motor is provided on the side is disclosed.

  Similarly, in Patent Document 3 (Japanese Patent Laid-Open No. 2007-055722), Patent Document 4 (Japanese Patent Laid-Open No. 2003-073009), and Patent Document 5 (Japanese Patent Laid-Open No. 2006-240761), the entire paper discharge tray is respectively described. An invention configured to be movable up and down is disclosed.

  In any case, the stacking efficiency of the discharged paper is improved by effectively using the limited space. However, in the invention described in Patent Document 1, the fixed side of the discharge tray is substantially horizontal. When stiff paper is stacked, even if the angle of the stacking surface of the paper discharge tray is changed, the paper may not follow the placement surface whose angle has been changed, and the paper discharge port may be blocked.

  Also, in the inventions described in the cited documents 2 to 5, since the entire tray moves, a large space is required below the image forming apparatus, and the leading end position of the sheet conveying direction varies depending on the posture of the tray even for the sheet outside the apparatus. Therefore, a space that does not interfere with the paper is required. Therefore, there has been a problem in miniaturization and space saving.

  Therefore, the problem to be solved by the present invention is to guarantee a stable paper discharge operation and a stacked state when paper is discharged in a limited space, and to improve reliability.

To solve the above problems, the present invention provides an image forming apparatus including a sheet stacking apparatus having a paper discharge tray for stacking the discharged sheets, said discharge tray becomes a fixed tray and allowed dynamic tray, The fixed tray is fixed on the downstream side in the paper conveyance direction, the movable tray is supported on the swinging fulcrum provided on the fixed tray on the upstream side in the paper conveyance direction so as to be swingable, and the fixed tray on the downstream side in the paper conveyance direction from the upstream side. It has an inclined paper stacking surface, and when the paper is not stacked or before full, the angle that the paper stacking surface of the movable tray makes with the horizontal direction is more than the angle that the paper stacking surface of the fixed tray makes with the horizontal direction. The sheet stacking device is set at a gentle angle, and is provided above the image forming apparatus main body and below the image reading device attached to the upper part of the image forming apparatus main body. , The swing fulcrum of the movable tray, with respect to the end face of the image reading apparatus located in the downstream in the sheet conveying direction, characterized in that it is arranged substantially vertically downward.

  In an embodiment described later, the image forming apparatus is denoted by reference numeral 100, the sheet processing apparatus is denoted by reference numeral 200, the image reading apparatus is denoted by reference numeral 300, and the sheet stacking apparatus is denoted by the discharge tray fixing portion 206 and the discharge tray movable portion 206a. The fixed tray corresponds to the discharge tray fixing portion 206, the movable tray corresponds to the discharge tray movable portion 206a, the swing fulcrum corresponds to the reference numeral 207a, the auxiliary tray corresponds to the reference numeral 206a, and the control board corresponds to the reference numeral 216.

According to the present invention, sheets are always stacked on the fixed tray in a constant state, and the user can easily determine how much sheets are stacked on the fixed tray .

1 is a diagram illustrating an outline of a system configuration of an image forming system according to an embodiment of the present invention. 1 is a front view illustrating a schematic configuration of a sheet processing apparatus. FIG. 6 is a diagram illustrating a state of a paper discharge tray when a small number of sheets are stacked. It is a figure which shows the state of the paper discharge tray at the time of full loading. FIG. 6 is a diagram for explaining a visually recognized state of a discharge tray. It is a figure for demonstrating the attachment angle | corner of a discharge tray. It is a figure which shows the example which has arrange | positioned the control board below the paper discharge tray.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1. Overall Configuration FIG. 1 is a diagram showing an outline of a system configuration of an image forming system according to an embodiment of the present invention. In FIG. 1, the image forming system according to the present embodiment includes an image forming apparatus 100, a sheet processing apparatus 200, and an image reading apparatus 300.

  The image forming apparatus 100 is an indirect transfer type tandem color image forming apparatus. In the figure, an image forming unit 110 having a four-color image forming station 111 disposed substantially in the center thereof is adjacent to the lower side of the image forming unit 110. The optical writing unit 111 provided below, the paper feeding unit 120 provided below the image forming unit 110, and the paper feeding conveyance for conveying the paper picked up by the paper feeding unit 120 to the secondary transfer unit 140 and the fixing unit 150. A path (vertical conveyance path) 130, a paper discharge path 160 for conveying the paper on which the image is fixed to the paper processing apparatus 200, and double-sided conveyance for reversing the paper on which an image is formed on one side and forming an image on the other side A path 170 is provided.

  The image forming unit 110 includes a photosensitive drum for each color of YMCK of the image forming station 111, and a charging unit, a developing unit, a primary transfer unit, a cleaning unit, and a charge eliminating unit arranged along the outer periphery of the photosensitive drum. And an intermediate transfer belt 112 for intermediate transfer of an image formed on the photosensitive drum by a primary transfer unit, and an optical writing unit 113 for writing an image for each color on the photosensitive drum. The optical writing unit 113 is disposed below the image forming station 111, and the intermediate transfer belt 112 is disposed above the image forming station 111. The intermediate transfer belt 112 is rotatably supported by a plurality of support rollers, and one of the support rollers 114 is opposed to the secondary transfer roller 115 via the intermediate transfer belt 112 in the secondary transfer unit 140, and the intermediate transfer belt 112. The upper image can be secondarily transferred to the paper. The image forming process of the indirect transfer tandem color image forming apparatus is well known and is not directly related to the gist of the present invention, and thus detailed description thereof is omitted.

  The paper feeding unit 120 includes a paper feeding tray 121, a pickup roller 122, and a paper feeding / conveying roller 123, and feeds the paper picked up from the paper feeding tray 121 upward along the vertical conveying path 130. The fed sheet is transferred with an image by the secondary transfer unit 140 and sent to the fixing unit 150. The fixing unit 150 includes a fixing roller and a pressure roller, and heat and pressure are applied in a process in which the paper passes through the nip between the two, and the toner is fixed to the paper.

  A paper discharge conveyance path 160 and a double-sided conveyance path 170 are provided downstream of the fixing unit 150, both of which are branched in two directions by a branching claw 161 and conveyed to the paper processing apparatus 200 side, and a double-sided conveyance path 170. The transport path is selected according to the case where the transport path is transported. A branch conveyance roller 162 is provided in the immediate vicinity of the branch claw 161 on the upstream side in the sheet conveyance direction, and applies a conveyance force to the sheet.

  The paper processing apparatus 200 is disposed inside the image forming apparatus 100, performs predetermined processing on the image-formed paper conveyed from the image forming apparatus 100, and stacks it on a paper discharge tray 203 positioned at the most downstream side. Details will be described later.

  The image reading device 300 is a known device that optically scans an original set on a contact glass and reads an image on the original surface. Since the configuration and function of the image reading apparatus 300 itself are known and are not directly related to the gist of the present invention, detailed description thereof is omitted.

  The image forming apparatus 100 configured generally as described above generates image data used for writing based on original data read from the image reading apparatus 300 or print data transferred from an external PC or the like, and the image data Based on the data, optical writing is performed from the optical writing unit 113 to each photosensitive drum, and the images formed for each color at each image forming station are sequentially transferred to the intermediate transfer belt 112, and are transferred onto the intermediate transfer belt 112. A color image in which images of four colors are superimposed is formed. On the other hand, paper is fed from the paper feed tray 121 according to the image formation. The sheet is temporarily stopped at a registration roller position (not shown) immediately before the intermediate transfer unit 140, sent in time with the leading edge of the image on the intermediate transfer belt 112, secondarily transferred by the intermediate transfer unit 140, and sent to the fixing unit 150. It is sent.

  In the case of single-sided printing or after double-sided printing of double-sided printing, the paper on which the image is fixed by the fixing unit 150 is transported to the discharge path 160 side by the switching operation of the branching claw 161, and in the case of double-sided printing. It is conveyed to the double-sided conveyance path 170 side. The sheet transported to the duplex transport path 170 is reversed, sent to the last intermediate transfer unit 140, an image is formed on the other surface, and then returned to the paper discharge path 160 side. The paper transported to the paper discharge path 160 is transported to the paper processing apparatus 200 and is subjected to predetermined paper processing by the paper processing apparatus 200 or discharged to the paper discharge tray 203 without processing.

2. Paper Processing Device FIG. 2 is a front view showing a schematic configuration of the paper processing device 200.
In FIG. 2, the sheet processing apparatus 200 includes an inlet roller pair 202, a rear end reference fence 212, a jogger fence 213, a stapler 215, a staple discharge roller 203, a tapping roller 210, a discharge roller 205, a sheet from the upstream side in the sheet conveyance direction. A rear end presser 208, a discharge tray movable portion 207, and a discharge tray fixing portion 206 are provided. The sheet processing apparatus 200 also includes a guide plate 201, a staple tray 209, a rear end return roller 211, and a paper discharge opening / closing guide plate 204. The paper discharge tray includes a paper discharge tray fixing unit 206 and a paper discharge tray movable unit 207.

  That is, a guide plate 201 that receives paper from the paper discharge conveyance path of the image forming apparatus 100 is disposed in the paper receiving portion of the paper processing apparatus 200, and the inlet roller pair 202 is disposed on the most upstream side in the paper conveyance direction of the guide plate 201. A pair of stapled paper discharge rollers 203 having a function of shifting the paper to the paper discharge tray T and discharging the paper is provided on the most downstream side, and the inlet roller pair 202 and the staple paper discharge roller pair 203 are rotated by an inlet motor (not shown). By doing so, the paper is conveyed along the guide plate 201. An inlet roller pair 202 and a staple paper discharge roller pair 203 provided along the guide plate 201 function as a conveying unit.

  The sheet discharge operation is different between the straight sheet discharge mode and the staple mode in which a plurality of sheets are bound and discharged.

<In straight output mode>
The paper enters from the guide plate 201 and is conveyed in the order of the entrance roller pair 202 and the staple paper discharge roller pair 203, and the paper discharge roller pair 205 that can hold the paper by closing the paper discharge opening / closing guide plate 204. The paper is discharged to the paper discharge tray T. When the paper is ejected, the discharge tray movable portion 207 is lowered once every several sheets, and when the rear end of the paper passes through the pair of paper ejection rollers 205, the rear end presser 209 has retreated to a position where it does not interfere with the rear end. The edge is pressed and comes up. The rear end presser 209 operates for each sheet. Although not shown, the rear end presser 209 detects the paper surface height.

<Stipple output mode>
The sheet enters from the guide plate 201 and is conveyed in the order of the entrance roller pair 202 and the staple discharge roller pair 203. After the sheet falls on the staple tray 209, the tapping roller 210 operates to move the trailing edge return roller 211. At the same time, the rear end of the sheet is brought into contact with the rear end reference fence 212 to perform vertical alignment (alignment in the transport direction). Then, the jogger fence 213 performs horizontal alignment (alignment in the direction orthogonal to the conveyance direction).

  The same operation is repeated until the final sheet. When the final sheet is stacked, the stapler 215 performs the binding process, the discharge opening / closing guide plate 204 is closed, and the sheet bundle is discharged to the discharge tray T by the discharge roller pair 205. The When the sheet discharge tray movable portion 207 is lowered once when the sheet is discharged, and the sheet bundle passes through the sheet discharge roller pair 205, the rear end is held by the rear end presser 209 that has been retracted to a position that does not interfere with the sheet discharge. Coming up.

  The paper discharge tray fixing unit 206 rotatably supports the paper discharge tray movable unit 207, and the paper discharge tray movable unit 207 moves up and down on the rear end side of the paper depending on the number of stacked sheets.

  As shown in FIG. 2, the swing fulcrum 207 a of the discharge tray movable unit 207 is positioned substantially vertically below the end surface portion I located on the downstream side of the image reading device 300 in the discharge direction (also referred to as the front end side of the sheet). Yes.

  Further, as shown in FIG. 5, by placing the swing fulcrum 207a substantially vertically below the end surface portion I, the sheet in the region II that can be easily seen on the discharge tray fixing portion 206 by the user. The stacked state is always stacked in a fixed state on the fixed paper discharge tray fixing unit 206. Thus, the user can easily determine how much paper is stacked on the paper discharge tray fixing unit 206.

  As shown in FIGS. 3 and 4, the angle α formed by the discharge tray fixing portion 206 and the discharge tray movable portion 207 is set to an obtuse angle when there is no stacking and before full loading. Further, the free end side of the discharge tray movable portion 207 descends according to the sheet stacking amount, and the angle β formed by the discharge tray fixing portion 206 and the discharge tray movable portion 207 is approximately 180 °, and the discharge tray fixing portion is fixed. When the portion 206 and the discharge tray movable portion 207 are substantially flat, a full load is detected by a detection means (not shown). The detection means may be any type such as a commonly used transmission type optical sensor and reflection type optical sensor.

  When the initial value of the angle formed by the paper discharge tray fixing unit 206 and the paper discharge tray movable unit 207 is set to a dominant angle β ′ (180 ° to 360 °), paper with strong stiffness and paper with large curl is discharged. Following the angle of the tray fixing unit 206, there is a possibility that the trailing edge of the paper does not follow even if the discharge tray movable unit 207 rotates. If the trailing edge of the sheet does not follow in this way, the stacking quality is deteriorated. However, in this embodiment, since the initial value of the angle α is set to an obtuse angle, the paper follows the movement of the discharge tray movable portion 207. As a result, it is possible to prevent a reduction in loading quality.

  Also, as shown in FIG. 6, the space inside the paper discharge tray when it is fully loaded is limited, and the storage of the auxiliary tray 206a that can be pulled out required for large-size loading is significantly hindered. Can be prevented.

  The angle of the paper discharge tray fixing part 206 is preferably 20 ° to 35 ° with respect to the horizontal, and the initial value of the angle α is preferably 140 ° to 160 °.

  In many cases, the sheet post-processing apparatus 200 is provided separately from the control board of the image forming apparatus 100. When the control substrate 216 is configured to enter the image forming apparatus 100, it takes time to remove the sheet post-processing apparatus 200 during maintenance. In addition, the internal temperature of the fixing unit 150 and the like is also greatly affected, and there is a concern about early deterioration.

  In order to eliminate such a concern, in this embodiment, the control board 216 is disposed below the paper discharge tray fixing part 206 as shown in FIG. This arrangement is made possible by fixing the paper discharge tray T. When the paper discharge tray T is arranged at the above position, if the paper discharge tray fixing portion 206 is movable, the control board 216 and the connector are interposed. Wires connected in contact with the paper discharge tray fixing unit 206 may cause a failure. In addition, in order to prevent the output tray fixing portion 206 from coming into contact with the wiring, the front and back of the control board 216 can be reversely attached. However, in such a case, access from below is required during maintenance. As shown in FIG. 7, the sheet post-processing apparatus 200 must be removed from the image forming apparatus 100. As a result, the maintenance is troublesome.

  However, since the discharge tray fixing portion 206 is fixed, there is no possibility that such a problem will occur.

As described above, according to the present embodiment,
1) By arranging the angle of the movable tray on the upstream side in the transport direction at a gentle angle with respect to the horizontal direction from the angle formed by the fixed tray on the downstream side in the transport direction, the rear end of the stacked sheets can follow the movable tray. This makes it possible to control the loading state to an ideal state.
2) Since the control can be performed as in 1), it is possible to provide a highly reliable paper stacking device that is stably loaded in a limited space.
3) By setting the angle of the fixed tray to be equal to that when the paper is fully loaded, the drawer tray stored in the fixed tray can be stored below the movable tray without interfering with the movable tray.
4) Since it can be stored as in 3), it is possible to minimize the protrusion of the drawer portion, and it is possible to efficiently stack sheets in a limited space.
5) Since the control board is placed in a space with a certain size and a favorable environment directly below the fixed tray, where there are few obstacles around the end in the transport direction and far from the heat source, the influence of the wiring fixed to the control board, Both the effects of temperature are reduced and reliability is improved.
6) Further, since access to the control board becomes easy, it is possible to provide an apparatus with high durability and good maintainability in a limited space.
There are effects such as.

  In addition, this invention is not limited to this embodiment, All the technical matters contained in the technical idea of the invention described in the claim are object.

DESCRIPTION OF SYMBOLS 100 Image forming apparatus 200 Paper processing apparatus 300 Image reading apparatus 206 Paper discharge tray fixing | fixed part 206a Auxiliary tray 207 Paper discharge tray movable part 207a Swing fulcrum 216 Control board 206T Paper discharge tray

JP 2008-110834 A Japanese Patent No. 4072515 JP 2007-055722 A JP 2003-073009 A JP 2006-240761 A

Claims (6)

An image forming apparatus including a paper stacking device having a paper discharge tray for stacking discharged paper,
It said discharge tray is fixed tray and allowed dynamic tray,
The fixed tray is fixed on the downstream side in the paper transport direction, and the movable tray is supported on the upstream side in the paper transport direction so as to be swingable on a swing fulcrum provided on the fixed tray,
The fixed tray has an inclined paper stacking surface whose downstream side in the paper transport direction is higher than the upstream side, and the angle that the paper stacking surface of the movable tray makes with the horizontal direction when the paper is not stacked or before full is fixed. It is set so that the paper stacking surface of the tray is at a gentler angle than the angle it makes with the horizontal direction.
The sheet stacking device is provided above the image forming apparatus main body and below an image reading device attached to the upper part of the image forming apparatus main body.
An image forming apparatus, wherein a swinging fulcrum of the movable tray is disposed substantially vertically downward with respect to an end surface of the image reading apparatus located on the downstream side in the sheet conveying direction. The image forming apparatus according to claim 1,
The movable tray descends according to the amount of paper loaded, and when the paper is full, the angle formed by the paper stacking surface of the movable tray and the paper stacking surface of the fixed tray is approximately 180 °. An image forming apparatus. The image forming apparatus according to claim 1, wherein:
An image forming apparatus comprising: an auxiliary tray that can be pulled out downstream of the fixed tray in parallel with a sheet placement surface of the fixed tray. The image forming apparatus according to claim 3, wherein
An image forming apparatus, wherein when the auxiliary tray is stored in a fixed tray, a part of the auxiliary tray is positioned below the movable tray. The image forming apparatus according to claim 1, wherein:
An image forming apparatus, wherein a control board is disposed below the fixed tray. The image forming apparatus according to claim 5, wherein
An image forming apparatus, wherein the control board is disposed so that a connector mounting surface faces upward.

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